#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)


int main() {
  string s;
  std::cin >> s;
  int a=int(s[0]),b=int(s[1]),c=int(s[2]);
  int maxx=max(max(a,b),max(b,c)),minn=min(min(a,b),min(b,c));
  std::cout << maxx-minn << '\n';
 return 0;
}